in output-sql (sql-relational-exp)-> made it not output anything if the relation...

diff --git a/sql/expressions.lisp b/sql/expressions.lisp
index aa9edcab98143431b00e3213906ea1fd01bbb605..d7a95ef74f83a11cd85ab96e69ed87af14cfe9ad 100644 (file)
--- a/sql/expressions.lisp
+++ b/sql/expressions.lisp
@@ -243,18 +243,20 @@
 
 (defmethod output-sql ((expr sql-relational-exp) database)
   (with-slots (operator sub-expressions)
-    expr
-    (let ((subs (if (consp (car sub-expressions))
-                    (car sub-expressions)
-                    sub-expressions)))
-      (write-char #\( *sql-stream*)
-      (do ((sub subs (cdr sub)))
-          ((null (cdr sub)) (output-sql (car sub) database))
-        (output-sql (car sub) database)
-        (write-char #\Space *sql-stream*)
-        (output-sql operator database)
-        (write-char #\Space *sql-stream*))
-      (write-char #\) *sql-stream*)))
+      expr
+    (when sub-expressions
+      (let ((subs (if (consp (car sub-expressions))
+                     (car sub-expressions)
+                     sub-expressions)))
+       (write-char #\( *sql-stream*)
+       (do ((sub subs (cdr sub)))
+           ((null (cdr sub))
+              (output-sql (car sub) database))
+         (output-sql (car sub) database)
+         (write-char #\Space *sql-stream*)
+         (output-sql operator database)
+         (write-char #\Space *sql-stream*))
+       (write-char #\) *sql-stream*))))
   t)
 
 (defclass sql-array-exp (sql-relational-exp)